C++14 support is now required.

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e97ab04..1af66cb 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -51,15 +51,15 @@ set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -g3")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g3")
 
 if (CMAKE_COMPILER_IS_GNUCC)    
-  if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS "4.7")
+  if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS "5.0")
     message(FATAL_ERROR
-            "SimGrid needs at least g++ version 4.7 to compile but you have ${CMAKE_CXX_COMPILER_VERSION}."
-            "You need a sufficient support of c++11 to compile SimGrid.")
+            "SimGrid needs at least g++ version 5.0 to compile but you have ${CMAKE_CXX_COMPILER_VERSION}."
+            "You need a sufficient support of c++14 to compile SimGrid.")
   endif()
 endif()
 
-## We need a decent support of the C++11 and C11 standards
-set(CMAKE_CXX_STANDARD 11)
+## We need a decent support of the C++14 and C11 standards
+set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 set(CMAKE_C_STANDARD 11)
@@ -427,8 +427,6 @@ if (enable_model-checking AND enable_ns3)
   message(FATAL_ERROR "Cannot activate both model-checking and ns-3 bindings: ns-3 pulls too much dependencies for the MC to work")
 endif()
 
-get_property(known_features GLOBAL PROPERTY CMAKE_CXX_KNOWN_FEATURES)
-
 if(enable_smpi)
   SET(HAVE_SMPI 1)
   if(WIN32)
@@ -793,47 +791,32 @@ if(enable_java)
   include(${CMAKE_HOME_DIRECTORY}/tools/cmake/Java.cmake)
 endif()
 
-if (enable_model-checking AND (NOT ("cxx_std_14" IN_LIST known_features)))
-  message(WARNING "C++14 not found. The model-checker will use a slow hash function. You should upgrade your compiler")
-else()
-  set_property(TARGET simgrid PROPERTY CXX_STANDARD 14)    
-endif()
-
 # Python binding (with pybind11)
 ################
-# Our usage of pybind11::overload_cast mandates C++14
 if((NOT DEFINED enable_python) OR enable_python)
-  if("cxx_std_14" IN_LIST known_features)
-
-    if(EXISTS ${CMAKE_HOME_DIRECTORY}/pybind11) # Try to use a local copy of pybind11, if any
-      message(STATUS "Use the internal copy of pybind11 (using C++14).")
-      add_subdirectory(${CMAKE_HOME_DIRECTORY}/pybind11)
-      set(pybind11_FOUND ON)
-
-      set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${CMAKE_HOME_DIRECTORY}/pybind11/tools/)
-      set(Python_ADDITIONAL_VERSIONS 3.7 3.6 3.5 3.4)
-      find_package(PythonLibsNew ${PYBIND11_PYTHON_VERSION} REQUIRED)
-
-    else()
-      find_package(pybind11 CONFIG)
-      message(STATUS "Pybind11 version: ${pybind11_VERSION}")
-      if (pybind11_VERSION VERSION_LESS 2.4)
-        message(STATUS "SimGrid needs at least v2.4 of pybind11. Disabling the Python bindings.")
-        set(pybind11_FOUND OFF)
-      endif()
-    endif()
+  if(EXISTS ${CMAKE_HOME_DIRECTORY}/pybind11) # Try to use a local copy of pybind11, if any
+    message(STATUS "Use the internal copy of pybind11.")
+    add_subdirectory(${CMAKE_HOME_DIRECTORY}/pybind11)
+    set(pybind11_FOUND ON)
 
-    if(NOT PYTHONLIBS_FOUND)
-      message(STATUS "Python libs not found. Turn pybind11 off.")
+    set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${CMAKE_HOME_DIRECTORY}/pybind11/tools/)
+    set(Python_ADDITIONAL_VERSIONS 3.7 3.6 3.5 3.4)
+    find_package(PythonLibsNew ${PYBIND11_PYTHON_VERSION} REQUIRED)
 
+  else()
+    find_package(pybind11 CONFIG)
+    message(STATUS "Pybind11 version: ${pybind11_VERSION}")
+    if (pybind11_VERSION VERSION_LESS 2.4)
+      message(STATUS "SimGrid needs at least v2.4 of pybind11. Disabling the Python bindings.")
       set(pybind11_FOUND OFF)
     endif()
+  endif()
+
+  if(NOT PYTHONLIBS_FOUND)
+    message(STATUS "Python libs not found. Turn pybind11 off.")
 
-  else()
-    message(STATUS "No support for C++14 detected, don't even search for pybind11.")
     set(pybind11_FOUND OFF)
   endif()
-  unset(known_features)
 endif()
 
 option(enable_python "Whether the Python bindings are activated." ${pybind11_FOUND}) # ON by default if dependencies are met
@@ -845,7 +828,7 @@ endif()
 
 if(enable_python)
   if(pybind11_FOUND)
-    message(STATUS "Found pybind11, with C++14.")
+    message(STATUS "Found pybind11.")
     if(NOT enable_lto)
       set(pybind11_options NO_EXTRAS)
     endif()

diff --git a/ChangeLog b/ChangeLog
index ce874a1..3ccecb9 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -25,7 +25,7 @@ S4U:
  - the on_exit() of each actor is also executed when the simulation deadlocks.
 
 SMPI:
- - Update proxy apps coverage of new ECP apps: 60+ apps now tested nightly on 
+ - Update proxy apps coverage of new ECP apps: 60+ apps now tested nightly on
    https://framagit.org/simgrid/SMPI-proxy-apps
  - MPI/IO: supports names starting with "./"
  - Fortran: many MPI/IO bindings, support for MPI_UB/LB, C MPI_INT/FLOAT/DOUBLE
@@ -39,6 +39,7 @@ C binding:
    (int value was previously ignored)
 
 General:
+ - Require a compiler with C++14 support.
  - LTO is now enabled for Intel/clang compilers.
  - LTO behavior on GCC can be parameterized using LTO_EXTRA_FLAG in cmake.
    Setting it to "auto" will use all available cores, while setting it to n will

diff --git a/FindSimGrid.cmake b/FindSimGrid.cmake
index 2902b52..1b18176 100644 (file)
--- a/FindSimGrid.cmake
+++ b/FindSimGrid.cmake
@@ -45,7 +45,7 @@
 #      (code to use with SimGrid v3.19+)
 #    #endif
 #
-#  Since SimGrid header files require C++11, so we set CMAKE_CXX_STANDARD to 11.
+#  Since SimGrid header files require C++14, so we set CMAKE_CXX_STANDARD to 14.
 #    Change this variable in your own file if you need a later standard.
 
 # 
@@ -58,7 +58,7 @@
 
 cmake_minimum_required(VERSION 2.8)
 
-set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 find_path(SimGrid_INCLUDE_DIR
@@ -117,22 +117,28 @@ if (SimGrid_FOUND AND NOT CMAKE_VERSION VERSION_LESS 2.8.12)
     INTERFACE_COMPILE_FEATURES cxx_alias_templates
     IMPORTED_LOCATION ${SimGrid_LIBRARY}
   )
-  # We need C++11, so check for it just in case the user removed it since compiling SimGrid
+  # We need C++14, so check for it just in case the user removed it since compiling SimGrid
   if (NOT CMAKE_VERSION VERSION_LESS 3.8)
     # 3.8+ allows us to simply require C++11 (or higher)
-    set_property(TARGET SimGrid::SimGrid PROPERTY INTERFACE_COMPILE_FEATURES cxx_std_11)
+    set_property(TARGET SimGrid::SimGrid PROPERTY INTERFACE_COMPILE_FEATURES cxx_std_14)
   elseif (NOT CMAKE_VERSION VERSION_LESS 3.1)
     # 3.1+ is similar but for certain features. We pick just one
-    set_property(TARGET SimGrid::SimGrid PROPERTY INTERFACE_COMPILE_FEATURES cxx_alias_templates)
+    set_property(TARGET SimGrid::SimGrid PROPERTY INTERFACE_COMPILE_FEATURES cxx_attribute_deprecated)
   else ()
-    # Old CMake can't do much. Just check the CXX_FLAGS and inform the user when a C++11 feature does not work
+    # Old CMake can't do much. Just check the CXX_FLAGS and inform the user when a C++14 feature does not work
     include(CheckCXXSourceCompiles)
     set(CMAKE_REQUIRED_FLAGS "${CMAKE_CXX_FLAGS}")
-    check_cxx_source_compiles("using Foo = int; int main(){}" _SIMGRID_CXX11_ENABLED)
-    if (NOT _SIMGRID_CXX11_ENABLED)
-        message(WARNING "C++11 is required to use SimGrid. Enable it with e.g. -std=c++11")
+    check_cxx_source_compiles("
+#if __cplusplus < 201402L
+#error
+#else
+int main(){}
+#endif
+" _SIMGRID_CXX14_ENABLED)
+    if (NOT _SIMGRID_CXX14_ENABLED)
+        message(WARNING "C++14 is required to use SimGrid. Enable it with e.g. -std=c++14")
     endif ()
-    unset(_SIMGRID_CXX11_ENABLED CACHE)
+    unset(_SIMGRID_CXX14_ENABLED CACHE)
   endif ()
 endif ()